"Nah, just Sans is fine. Unless it's funny." Sans will play uncle for the bit, but he doesn't want John to expect anything. The fewer people expect things from him, the better. He says this even knowing that Papyrus might also expect Sans to do things in regards to John, which is... Harder for Sans to ignore.

That's a problem for later. Ideally never, but he's pretty great at putting things off.

"You just gotta act how everybody expects out in public. And, y'know, don't do anything weird in front of any open windows. Not that you seem like the weird type." Which is its own brand of weird, in Sans's opinion, but at least one that makes things easier on Papyrus, he hopes. "Everybody who showed up like us is on this street, so far, so you don't have to go far if you want to get to know actual people."

Sans doesn't exactly classify the natives as real. Not exactly fake, either, but--something else.